Process and apparatus for applying shields to pipes



June 16, 1936. F. w. YEAGER PROCESS AND APPARATUS FOR APPLYING SHIELDSTO PIPES Filed Jan. 27, 1934 2 Sheets-Sheet l P R Y WV R W m ilk A ZJune 16, 1936. E E 2,044,456

PROCESS AND APPARATUS FOR APPLYING SHIELDS TO PIPES Filed Jan. 27, 19342 Sheets-Sheet 2 INVENTOR Frank VI! Yeager BY I W ATTO R N EY PatentedJune 16, 1936 @NHTE STATES PATENT Paocass m APPARATUS roa'arravme smms'ro rrrns Application January 27, 1934, Serial No. 708,584, 13 Claims.(01'. 154-2) 5 tective material, such as bitumen-pr resin-sattheabrasive or other action of materials with urated felt, paper, or clothor other types of satwhich the pipe comes in contact. Even a smallurated or unsaturated flexible shields, around a abrasion in theprotective film will permit the in- P P gress of injurious substances tothe walls of 'the One object of the invention is to provide an impipewith consequent deterioration thereof. In

proved method and apparatus for placing a layer order to prevent suchlocalized corrosion, it is es-- of protective sheet material around apipe while sential that the continuity of the protective film employinga minimum quantity of said protective or coating be preserved. Withburied pipes this sheet material. is especially dlfiicult, sincealthough the pipes Another object of the invention is to provide may belaid with the greatest possible care, suban improved pipe-shieldapplying apparatus sequent soil stresses or movements may deform adaptedto be moved longitudinally along the top and abrade the protectivecoating with resultant of a horizontal non-rotating pipe. Thisappaexposure of portions of the pipe. By soil stresses, ratus requiresvery little clearance around the we mean those agencies of motion in asoil which pipe, thus eliminating the necessity of jacking up exertmechanical forces, almost entirely of a disthe pipe to any considerableheight. advantageous nature, against anything placed- Another object ofthe invention is to provide a or buried in the soil. -In such a categorywould machine for applying a flexible shield around a be classedpipe sothat the edges of the sheet overlap in a 1. Destructive effects of back,fill striking single continuous joint extending longitudinally againstmaterial being buried;

5 along the bottom of the pipe. 2. Settling of soil;

Other objects and advantages will appear from 3. Expansion and shrinkageefiect produced the following detailed description of the invenin soilby tion. (a) Wetting and drying Owing to the corrosive action of varioussub- (b) Freezing and thawing;

stances present in the atmosphere or in the soil, 4. Earth vibrationsand slides;

pipe lines, especially those of iron or steel, are 5. Motion of heavysubstances, as rock, etc., subject to rapid deterioration. The life ofunthr wn' n son; protected pipes varies, depending upon the par- 6. Thesuction of quicksands, colloidal clays, ticular conditions to which theyare subjected. mud, e. g. gumbo mu Numerous factors may take part in thecorrosive In order to prevent the rapid deterioration of or erosiveaction and the rate of deterioration pipe lines such lines have beencoated with bimay be the resultant of a number of these factors tuminousenamel or other protective coating and acting together. Thus, withunderground pipe the coated pipe wrapped by means of a rotating 40 linesthe efiect of alkaline or acid substances in appar tus which winds astrip of saturated porous This invention relates to the protectionagainst deterioration of pipes or other tubular articles hereinafterreferred to as pipes and especially relates to a machine and method forapplying prothe water which reaches the pipe by seepage, and the efiectof electrolysis and ground currents or other agencies may be such that apipe will have a relatively short usefullifef If the pipes are coatedwith protective coatings such as bituminous enamel or the like, theeffect of soil stresses or movements frequently is-such as to remove ordamage the enamel at one or more points and expose the pipe to thedestructive actions mentioned. If the pipe is exposed'to the atmosphere,the composition of the gases, water, etc., contacting with it may besuch that the pipe rapidly deteriorates and must be replaced long beforereplacement would ordinarily 'be necessary.

Pipes (whether of iron, steel, or other metal, concrete, wood, or othermaterial) which are to be used under such unfavorable conditions arefrequently provided with a protective film of bituminous or otherenamel, paint, or varnish, but such films are more or less readilyremoved by material, such as tar-or asphalt-saturated rag or asbestosfelt, spirally therearound. Such spiral wrappings, it will beappreciated, involve a considerable waste of material due to the lappro-' vided between the large number of contiguous windings necessary tocover the pipe. 5

In employing such rotating apparatus, it was" necessary to jack up thepipe off the ground, or in the case of fixed lines, 1. e., lines,already in place in the field, above the top of the trench to aconsiderable height in order to allow ample clearance for the wrappingmachine to pass under the pipe during its rotation. The jacking of thepipe to provide the necessary clearance overthe trench or groundinvolved arduous and time-consuming labor.

According to my invention, a shield or sheet of flexible wrappingmaterial is bent or folded around the top of the pipe and lapped andjoined together in a single straight line extending along the bottom ofthe pipe. The lapping and joining is done by a simple machine whichtravels longitudinally along the top of the stationary pipe and does notrotate therearound. The width of the shield or wrapper employed isusually about two or four inches greater than the circumference of thepipe so that a 2" or 4" lap is produced.

Since the lap formed with my apparatus follows a single straight lineextending longitudinally of the pipe, a minimum of pipe-shield materialis required per unit length of pipe covered. When using a rotatingapparatus and wrapping the pipe with aspiral joint, as has heretoforebeen done, a considerably greater quantity of material had to beemployed due to the increased length of the lap per unit length of pipecovered.

As a shield I prefer to use a sheet of fibrous material, such as paper,felt, woven or knitted cloth, or the like, impregnated. with abituminous saturant, such as coal tar pitch, or a resin, such, forexample, as a condensation product of formaldehyde and a phenol, such asphenol, cresol, xylenol, or mixturesthereof. Any material impartingtothe base sheet imperviousness, hardness, and resistance to' tearing orpuncture while yielding a sheet suitable for bending around the pipe maybe employed as the impregnating agent.

If desired, the shield may be built up of a number of laminations ofimpregnated materials, either similar or dissimilar materials being usedfor different laminations, but the thickness of the shield should not beincreased to such an extent that its flexibility will be materiallyimpaired. In some cases it may be desirable to use a shield comprisingan impregnated base sheet having a reinforcing sheet such as paper orfelt, applied thereto.

For a better understanding of the invention reference should be made tothe accompanying drawings wherein is shown by way of illustration apreferred embodiment of the invention. In the drawings:

Fig. 1 is a side elevation of a shield-applying apparatus embodying thisinvention showing it in working position on a section of pipe, wrappinga shield around the pipe;

Fig. 2 is a plan view of the apparatus of Fig. 1;

Fig. 3 is a sectional elevation taken along the line 3-3 of Fig. 1showing the driving mechanism for propelling the apparatus along thepipe;

Fig. 4 is an enlarged sectional elevation taken along the line 4-4 ofFig. 1 showing the forward end of the cone shaped lapping device bendingthe edges of shield into lapped position around the pipe;

Fig.5 is an enlarged sectional elevation taken along the line 5-5 ofFig. 1 showing the funnel for applying cementing material between thelapped edges of the shield;

Fig. 6 is anenlarged sectional elevation taken along the line 6-6 ofFig. 1 showing the rear end of the lapping device and the spring forholding the two sections of the device together aroundthe pipeandshield;

Fig. 7 is a front elevation of the carriage for holding the rollofshield and showing the carriage in place on the pipe;

Fig. 8 is a side elevation of a modified shieldapplying apparatusembodying this invention showing the apparatus in working position on asection of pipe, wrapping a shield around the p pe;

Fig. 9 is a plan view of the apparatus of Fig. 8; and

Fig. 10 is a sectional elevation taken along the line Ill-I0 of Fig. 8showing the arrangement of the carriage for holding the roll of shield.

Referring to the drawings with special reference to Figs. 1 and 7,numeral l indicates a section of pipe held a short distance above theground by any suitable means, such as skids or jacks (not shown).Numeral 3 denotes a stand or carriage mounted on the pipe and carrying aroll 5 of pipe wrapping material 1.

Carriage 3 comprises a flat horizontal base 9 having verticaltriangular-shaped side pieces I I welded or otherwise secured thereto.Each of these side pieces is provided at its top or apex with a bearingI3 supporting a removable spindle l5 carrying the roll 5 of pipe shieldor pipe wrapping material. The bearings may be U- shaped, as shown inthe drawings, although any other type permitting the ready removal ofthe spindle and the placement of the roll of shield thereon may beemployed. Guide discs I1, having set screws l9 passing through theirhubs, permit the roll of shield or wrapping material to be readily andsecurely positioned on the spindle. Tautness or tension on the shieldleaving the roll can be regulated by adjusting the pressure of the discsagainst the ends of the roll.

As shown in Fig '7 the base 9 and spindle [5 should be of widthsufficient to carry a roll of shield having a width 2 to 4 inchesgreater than 1 the circumference of the pipe. One size of carriage isgenerally used at various times for supplying wrapping material toseveral sizes of pipe, the size of the pipe on which any one machine canbe used being limited by the length of the spindle, i. e., by the sizeof the roll which it can carry.

Brackets 2| are attached to the under side of the base by bolts 22 or byother suitable means such as rivets or welding. As shown in Fig. 7 twoof these brackets are provided, each extending longitudinally of thebase 9 on either side of the center line thereof. Each bracket isprovided at each end with a wheel support 23 carrying an idler wheel 24adapted to rest on the top of the passing through the longitudinalcenter lineof the pipe.

Grips or handles 26 are attached to both sides of base 9 and provide aready means by whicn workmen may hold the carriage on the pipe and pushit therealong when in use. A strut 21 is pivotally and removablyconnected to a bracket 28 on base 9 by means of a bolt and nut 29 orother suitable attaching means. By resting the lower end (not shown) ofthe strut 21 on the ground the carriage 3 may be supported in opezatingposition on the pipe. The strut is preferably made of variable length sothat it may be adjusted to conform with the height of the carriage abovethe ground. For example, the strut may be made in two sections 30 and30. movable longitudinally with respect to each other and held togetherin the desired relationship by a clamp 3|.

.Numeral 32 designates in general the apparatus for folding and wrappingthe sheet of flexible wrapping material unreeled from carriage 3 aroundthe pipe. This device has a housing or body portion 33 adapted toencircle the pipe and having the general shape of a truncated cone. Theforward end of the housing is flared outward to permit the sheet offlexible wrapping material to pass between the interior surface of thecone and the circumference of the pipe as the housing is moved along thepipe.

The housing is composed of two side walls or side pieces 35 and 36 ofgenerally semi-cylindrical cross-section swingably connected together atthe top by a hinge 31. Side walls 35 and 35 are preferably made of sheetsteel or other durable and more or less flexible material. The sidewalls are held together at the bottom by tension springs 39 stretchingbetween pins GI and 32 attached to side walls 35 and 36 respectively atthe middleportions and rear ends thereof. Each spring can bedisconnected from one or both pins thus permitting the cone-shapedhousing to be swung open on the hinge and placed around or taken off apipe. These springs hold the rear end of the housing or body portionmore or less firmly in place around the pipe and produce s" ientpressure to bend the flexible shield are id the pipe. As shown in Figs.4 to 6, the edges of the side pieces overlap to a certain extent. Thispermits the sides of the housing to move toward or away from one anotheras the apparatus passes over welds or other uneven portions of the pipeand at the same time insures that the bottom of the housing will alwaysbe closed.

Side pieces 35 and 36 are each provided with a slot, designatedrespectively by numerals 43 and 4d, the purposes of which are discussedbelow. As shown in Fig. 2, slot 43 is preferably made somewhat longerand wider than slot 84.

A clamp or bracket 65, riveted or otherwise secured to the side piece 35at a point ne r its longitudinal mid-portion, supp rts a tube 46, oneend of which extends into the interior of the coneshaped housing througha hole 41 in side'piece 35 near its lower end. A cylindrical shapedfunnel 48, provided with a valve 39, has its discharge spout l fittinginto the other end of tube 46.

Numeral 53 indicates in general a driving mechanism for moving thecone-shaped housing or body portion of the apparatus longitudinallyalong the pipe around which it extends. This driving mechanism has atriangular shaped frame 55, base 58 of which is rigidly attached to thetop of side piece 35 adjacent the hinge 31. Rotatably mounted in theforward portion of the triangular frame near the base thereof is a shaft51 having wheels 59 mounted thereon in such position that the lowerportions of the wheels pass through slots 49 and 44 in the housing.These wheels are preferably rubber tired in order to prevent possibleinjury to the shield, resting on the upper surface of the pipe, withwhich they contct through slots 43 and 44 and over which they pass. Asshown in Figs. 2 and 3, one end of this shaft has a sprocket wheelGlkeyed thereon. The top or apex of the triangular frame supports arotatable shaft 63 having a crank 65 fixed to one end and a sprocketwheel 61 to the other. A sprocket chain 69 passes around sprocket wheelsBI and 61. As the crank 65 is turned, sprocket wheel 6'! is rotated andchain 89 moved driving sprocket wheel 6|. Movement of the sprocket wheelcauses shaft 51 to rotate revoiving wheels 59 attached thereto. Rotationof wheels 59 causes the entire apparatus to move longitudinally alongthe pipe.

A bar Ill, extending horizontally from near the apex of triangularframes 55, provides a handle or grip by means of which the drivingmechanism 53 and the entire folding apparatus 32 may be held in thedesired position on the pipe. Numeral l2 designates a. strut swingablyand removably connected to an arm 13 extending from base 56 of frame 55.This strut may have a construction similar to strut 27 on the pipeshield carriage 3, and provides a means whereby the folding apparatusmay be supported on the pipe without manual aid when the apparatus isnot in use or being repaired or adjusted.

The operation of the apparatus in applyin' a shield to a pipe is asfollows:

A roll of suitable pipe shield material of a width 2 to 3 inches greaterthan the circumference of the pipe to be wrapped is inserted on thespindle E5 of carriage 3 and the, guide discs 47 adjusted to allow theshield to be unwound from the roll with the proper amount of tension.The carriage is then placed on the top of the pipe and the wheelsupports 23 adjusted relative to brackets 2| by means of bolts 25 sothat the idler wheels on each side of the carriage lie in planes passingthrough the center line of the pipe. The carriage is then movedlongitudinally along the top of the pipe by workmen so that some of thewrapping material or shield is unreeled along the top of the pipe asshown in Figs. 1 and 2.

A portion of the flexible shield lying on the top of the pipe is thenbent around the circumference of the pipe by hand so that the marginalportions of the shield overlap along the-bottom of the pipe. Thecone-shaped housing 33 of the shield-applying apparatus 32 is thenopened up on its hinge and fitted around the overlapped shield and pipe.Slot 63 in sidewall 35 is of such size as to provide clearance spacepermitting swinging of the side wall 35 on hinge 31. The springs 39 arethen attached to pins ll and 32 thus causing the lower ends of the sidesof the housing to be held together around the pipe and shield as shownin Figs. 4 to 6. Since the forward end of the cone-shaped housing isflared away from the pipe, the shield is not held tightly against thepipe at this point (Fig. 4). At the rear end of the apparatus, however,the springs hold the sides of the housing firmly against the shield andcause it to fit snugly against the pipe (Fig. 6).

When the apparatus is in place, crank 65 of the driving mechanism isturned by a workman thus causing wheels 59 to rotate and the entiredevice to move along the pipe and shield thereon at a suitable. rate.Simultaneously, the carriage carrying the roll of shield is moved byworkmen along the pipe in front of the folding apparatus atsubstantially the same rate thereby unreeling the shield or wrapperalong the top of. the pipe in front of the folding apparatus. As thefolding apparatus is moved continuously and progressively along thestationary pipe, the cone-shaped housing bears against the flexibleshield and causes it to be continuously and progressively bent downwardaround the pipe and overlapped by the conver'ging'interior surface ofthe cone in a. substantially straight line along the bottom of the pipe.

effected by traction pulleys similar to those shown on unit 32 andoperated similarly, but mounted on unit 3, or in other ways.

A supply of hot fluid cementing material, such as coal-tar pitch orasphalt, is introduced into funnel 48. Valve 49 in the discharge spoutof the funnel is opened so that a continuous stream of the cementingmaterial flows through tube 46 into the interior of the housing. Asshown in Fig. 5, the tube 46 is so situated that the cementing isapplied between the loosely overlapped marginal portions of the shield.As the apparatus continues to move, the rear end of the cone or housingbears firmly against the shield and pipe and causes the cemented lappedportions of the shield to become securely joined together. There is thusproduced a strong and effective shield around the pipe having a singlejoint therein extending longitudinally along the bottom of the pipe.

Instead of applying cementing material to hold the overlapped portionsof the shield together, the lap may be joined by other means, such asmechanical fasteners or clamps. In this case the fasteners or clamps areapplied to the shield at a point immediately following the rear end ofthe housing.

When using larger apparatus suitable for applying shields to largerpipes, it is sometimes desirable to equip the apparatus with a smallpower unit for moving the apparatus along the pipe.

It should also be understood that the roll of shield may be carried on aframe supported from the front of the folding frame thus eliminating theseparate carriage. An apparatus having such construction is shown inFigs. 8 to 10. This modified device is in general similar to the foldingapparatus 32 described above, with the exception that the drivingmechanism 53 is placed further toward the rear of the housing to provideroom for the shield carriage, denoted by reference character 15.

A saddle-shaped member 16 fits over and is attached to the upper portionof housing 33 in any suitable manner. Braces 11 extend upward from bothsides of this saddle member and hold base 9 of the carriage securely inplace. Vertical side pieces I l secured to base 9 are provided withbearings I3 supporting spindle l5 carrying the roll 5 of pipe shield I.A triangular shaped frame 18 extends forward from each side piece I l.The extremities of these frames are provided with bearings 80 supportingan idler roll 8| over which the sheet of wrapping material I is adaptedto pass from roll 5 before being folded around the pipe.

Instead of having just one hinge extending movement.

*greatest .possible protection from subsequent damage due to handlingand soil stress. Furthermore, the apparatus of this invention requiresmuch less clearance above the ground or trench for satisfactoryoperation than was required by apparatus rotating around the pipe andapplying a spiral wrapping.

Since certain changes in carrying out the process and in theconstruction set forth may be made without departing from the scope ofthis invention, it is intended that all matter contained in theabovedescription or shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

I claim:

1. Apparatus for applying a flexible shield to a pipe comprising ahousing adapted to fltaround the pipe and fold the shield therearound,and

, means for moving said housing along the pipe.

2. Apparatus for applying a flexible shield to a pipe comprising ahousing adapted to encircle the pipe and fold the shield therearound,and a driving mechanism connected to the housing, said driving mechanismbeing adapted to move longitudinally along the top of the pipe.

3. Apparatus for applying a flexible shield to a pipe comprising ahousing adapted to fit around the pipe and fold the shield therearound,said housing having two curved side walls, means joining the tops ofsaid side walls, and a driving mechanism for moving the housing alongthe pipe.

4. Apparatus for applying a flexible shield to a pipe comprising a.housing adapted to fit around the pipe and fold the shield therearound,said housing having curved side walls, means joining said side walls,removable means connecting said side walls and holding the wallstogether around the pipe, and means for moving the housing along thepipe.

5. Apparatus for applying a flexible shield to a pipe comprising ahousing adapted tofit around the pipe and fold the shield therearound,said housing having two side walls of substantially semi-circularcross-section swingably joined by a hinge and held together at thebottom by a spring, and means for moving said housing along the pipe.-

6. Apparatus for applying a flexible shield to a pipe comprising acone-shaped housing adapted to encircle the pipe and fold the shieldtherearound, said housing having side walls swingably joined and heldtogether at the bottom by a removable means, a tube passing through oneside wall of the housing for introducing cementing material into theinterior thereof, and means for moving the housing along the pipe.

'7. Apparatus for applying a flexible shield to a pipe comprising ahousing adapted to encircle the pipe and fold the shield therearound,said housing having two side walls of substantially semi-circularcross-section, a hinge connecting the tops of said side walls, aremovable spring joining the bottoms of said side walls, a funnelattached to one of said side walls, a tube leading from said funnel andpassing through a hole near the bottom of the side wall for introducingcementing material into the housing, and means for moving said housingalong the pipe.

.8. Apparatus for applying a flexible shield to a pipe comprising acone-shaped housing adapted to fltaround the pipe and bend the shieldtherearound so that the marginal portions of the shield overlap alongthe bottom of the pipe, said housing having two side walls ofsubstantially semicircular cross-section, a hinge connecting the tops ofsaid side walls, a spring adapted to hold the bottoms of said side wallsin place around the pipe and shield, a funnel attached to one of saidside walls, a tube leading from said funnel and passing through a holenear the bottom of said side wall for introducing cementing materialinto the interior of the housing, and a hand-operated mechanism attachedto one end of the housing for moving the housing along the pipe.

9. Apparatus for applying a flexible shield to a pipe comprising ahousing adapted to encircle the pipe and fold the shield therearound, adriving mechanism connected to the housing adapted to move said housinglongitudinally along the pipe, means on said housing for supporting aroll of flexible shield, and means for feeding the shield onto the pipein front of the housing as the housing moves along the pipe.

10. Apparatus for applying a flexible shield to a pipe comprising ahousing adapted to encircle the pipe and fold the shield therearound,said housing having flexible side walls, a hinge swingably connectingsaid side walls, removable means adapted to hold said side wallstogether around the pipe, a tube passing through one side wall forintroducing cementing material into the interior of the housing, meanson said housing for moving the housing along the pipe, and means on saidhousing for supporting a roll of flexible shield.

11. The process of shielding a stationary pipe which comprises placing ashield longitudinally along the top of the pipe, resiliently forcing thesides of the shield around the circumference of the pipe so that theedges of the shield form a lap along the bottom of the pipe, applyingcementing material between the lap, and pressing the lap together.

12. The process of shielding a pipe which comprises continuously andprogressively unwinding a roll of shield along the top of a pipe,continuously, progressively and resiliently forcing the shield around apipe, continuously and progressively overlapping the edges of the shieldin a straight line extending along the bottom of the pipe, continuouslyand progressively applying cementing material between the lapped edgesof the shield, and continuously and progressively pressing the lappededges of the shield together.

13. In a device for applying shielding material to pipe, a housingadapted to fit around and to be moved along the pipe, said housinghaving one side extending substantially parallel 2- to the longitudinaldirection of the pipe and a side remote from said first mentioned sideflaring away from the pipe at one end of the housing.

FRANK W. YEAGER.

